1. Field of the Invention
The invention relates to a method of transforming user manipulations of a multidimensional input device into code vectors for a data processing apparatus, the manipulations being confined to a range around an origin, the method comprising the steps of: (1) dividing the range into a plurality of subranges; (2) assigning a unique code vector to each subrange; and (3) for a particular manipulation, determining a corresponding particular subrange and selecting a corresponding particular code vector for transmission to the data processing apparatus. The invention further relates to a system and a multidimensional input device for carrying out such a method.
2. Description of the Related Art
A method as specified in the preamble is known from German Offenlegungschrift DE-A 35.23.284. In that document, an input device is described that is used for updating one or more parameters in a data processing apparatus (e.g., co-ordinates of a pointer on a screen). According to that document, a manipulation of the input device is not directly translated to a corresponding parameter value, but to a rate of change of that value. The actual updating is performed in the data processing apparatus. The latter is provided with input data indicative of the manipulation. Hereto, the input device transforms the manipulation into particular input data (further referred to as a code vector), representing the manipulation. Subsequently, the code vector is sent via some kind of communication channel (cable, wireless) to the data processing apparatus. There, a decoder is present to decode the received code vectors into data that can be handled by the data processing apparatus.
In a two-dimensional variant of the known input device, the user manipulation is essentially projected on two orthogonal axes (an X-axis and a Y-axis). From the projections, a code vector is constructed and transmitted that comprises digital representations of the projections.
A special field of application of such input devices is in the area of remote controls, such as, TV remote controls. Remote controls have their own, limited, power supply (battery). A significant amount of power is required for transmitting the code vectors to the data processing apparatus. Therefore, in order to extend battery-life, power can be saved by minimizing the amount of information to be sent to the data processing apparatus. At the same time, the user has to be offered convenient control over the parameter to be adjusted. The latter is determined by aspects such as speed of parameter update, accuracy of parameter update and, in case of a multidimensional input device, convenient simultaneous control over more than one parameter (for example, moving the pointer over the TV screen).
A problem of the known method is that power considerations have not been given attention. Consequently, the known method does not transform the manipulations into efficient code vectors, from a power point of view.